With a few exceptions NHL is the league that collects the best players from all around the world. But AFAIK almost all the coaches are from USA or Canada. I understand why that's the case, but it also means there can be some excellent coaches and good fresh ideas in other leagues too.
In fact I'd like to say the quality of coaching in the FEL is very high and while we're talking about a league with much worse players there are some things going on that maybe deserve a closer look. The quality of the coaches has also helped the national team do better than it maybe should've quite a few times.
A few FEL coaches stand above the others and there are usually some common denominators. Those coaches play modern hockey (with variation when needed), let their players learn from mistakes throughout the season, react during the games, listen to the players and develop them individually and even make sure they live and train professionally.
While I recognize the best NHL coaches are maybe the best ones in the world I believe many coaches don't get even close to maximizing their team's potential. To me McLellan's style looks egoistic, lazy or the both. It may work with a stacked team with a lot of veterans, but I don't see the current Oilers as a good fit. It may work to some extent as long as the team does well and he's got the players' respect.